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1.
单柱离子色谱法测定茶叶中草酸根和硫酸根的研究   总被引:1,自引:1,他引:1  
本文研究单柱离子色谱分离测定茶叶中微量草酸根和硫酸根的方法。样品水浸泡,酸化液。上ShimParskIC-A_2柱分离,用2.0mmol·L ̄(-1)H-2C_8O_4/1.9mmol·L ̄(-1)Tri淋洗液洗脱,电导检测器检测,检测灵敏度为1.6S/cm,最低检出限0.05μg/mL;线性范围L;相对标准偏差1.06%;平均回收车98.72%97.88/。该法简便、快速、准确、灵敏、选择性好。  相似文献   

2.
不完全抑制电导检测离子色谱法测定饮料中的苹果酸   总被引:2,自引:0,他引:2  
朱岩  徐素君  王素芬 《分析化学》1999,27(9):1050-1053
采用一种抑制型离子色谱检测技术--不完全抑制电导检测,以0.75mmol/LNa2SO4+NaOH(pH=11.5)为淋洗液对弱酸根离子如苹果酸、酒石酸等进行了测定,得到苹果酸、酒石酸的检测限分别为1.31mg/L、3.04mg/L;在200mg/L以下相关系数分别为0.9998、0.9999;;各离子峰高的相对标准偏差(RSD)分别为0.57%、1.60%。上率为97.7 ̄104%。常见的强酸离  相似文献   

3.
以酒石酸-乙二胺为淋洗液的单柱离子色谱法同时测定磷酸中痕量钠(Ⅰ)和铁(Ⅲ)。淋洗液最佳浓度为4.0mmol.L ̄(-1)、酒石酸/1.0m mol·L ̄(-1)乙二胺。最低检测限为Na ̄+0.05μg/mL、 Fe3+ 0.45μg/mL。电导检测灵敏度为2.0μg/cm。线性范围Na ̄+、Fe3+0.2~1.5×103μg/mL、2.5~1.0×103μg/mL。相对平均偏差Na ̄+为2.03%、Fe3+为0.83%。平均回收率Na ̄+为98.26%、Fe3+为97.62%。本法简便、快速、准确、选择性好。  相似文献   

4.
高效液相色谱法测定除草剂中二氯喹啉酸的含量   总被引:1,自引:0,他引:1  
本文报道酸抑制反相色谱法测定除草剂中二氯喹啉酸的含量,该法采用PC8-10/S2504(4.0mmi.d.×250mm,10μm)柱,以甲醇-0.1%醋酸为流动相,紫外检测波长为240nm,0.08AUFS,以2,4-二硝基氯苯为内标物,样品用四氢呋喃提取,该法灵敏度及回收率高,结果定量准确,操作简便可靠。  相似文献   

5.
本文报告了在0.01mol/LCTAB体系中,以F-为掩蔽剂、苯芴酮显色、用分光光度法测定饮料食品中Ge-132含量,最低检测限0.054μg/mL;线性范围0.54~27.14μg/mL;回收率96.3%~101.5%,并确定了Ge-132摩尔吸收系数(ε)3.39×104。用本法测定了康寿茶、矿泉水和博士奶中Ge-132含量,灵敏度高、重现性和准确度好。用盐酸化本体系,研究了二氧化锗(Ge~(4+))的含量测定,其最低检测限0.021μg/mL;线性范围1.0~21.0μg/ml;回收率95.8%~102.8%,Ge-132不干扰。饮料食品中同时存在Ge-132和Ge(4+)时,本体系可分别测定两者含量。  相似文献   

6.
反相高效液相色谱法测定杀虫剂中吡虫啉的含量   总被引:5,自引:0,他引:5  
报道了反相色谱法测定杀虫剂中吡虫啉的含量,该法采用YWG-C18(250mm×4.0mm,10μm),柱,以甲醇-水(含0.1%二乙胺,pH5.0),(35:65,V/V,1.0mL/min)为流动相,紫外检测波长为270nm,0.16AUFS,样品可直接用甲醇超声提取。样品中吡虫啉平均回收率≥97.43%,相对标准偏差≤2.1%。  相似文献   

7.
以1-(2-噻唑偶氮)-2-萘酚(TAN)作柱前显色剂,于ODS柱上,用内含0.1mol/LLiCl,5×10-6mol/L TAN和HAc-NH4Ac缓冲溶液(pH 5.5)的甲醇-水溶液(80:20,V/V)作流动相,流速为0.6mL/min,并以紫外-可见检测器于590nm处进行检测,发展了一种RP-HPLC法同时分离测定铜(Ⅱ)、铁(Ⅱ)、镍(Ⅱ)的方法,方法灵敏度高,对于铜、铁、镍的检测限分别为1μg/L, 2 μg/L和 0.4 μg/L。用于实际样品测定,结果满意。  相似文献   

8.
反相高效液相色谱法测定氟离子   总被引:8,自引:0,他引:8  
丁朝武  李华斌 《分析化学》1998,26(3):369-369
1引言本文建立了反相液相色谱测定氟离子的方法,与分光光度法相比,可将含氟络合物与试剂分离开,大大提高了测定的灵敏度和选择性。测定条件为Shim-PackCLC-ODS(6×150mm5u);流动相:甲醇-水(18:82);流速:1mL/min;柱温:35℃;检测波长:566nm。线性范围0.050~1.0mg/L;相关系数r=0.9991;检测限为0.001mg/L;相对标准偏差为1.9%~2.7%;回收率为97%~98%。本方法初步用于矿泉水和食盐等样品的测定,均取得较好的效果。2实验部分2.…  相似文献   

9.
反相高效液相色谱分离—安培法检测酚类化合物   总被引:4,自引:0,他引:4  
辛梅华  徐金瑞 《分析化学》1994,22(5):505-508
本文报道了RP-HPLC-安培法检测测定酚类化合物的条件,在Shim-packCLC-C8柱上用含0.5mol/L NaH2PO4缓冲溶液的5%甲醇水溶液洗脱分离,于E+1.0V处检测,线性范围在0-7μg/ml,检测限达ng/ml。  相似文献   

10.
离子色谱法测定α—氧化铝中微量硫酸根的研究   总被引:1,自引:0,他引:1  
吴介达  吕伟 《分析化学》1994,22(2):172-174
本建立了用氢氧化钠溶样,离子色谱测定α-Al2O3中微量硫酸根的方法。在DionexAS4A分离柱上,用1.8×10^-^3mol/LAa2CO3作流动相进行洗脱,电导检测器检测,分析方法简便,快速,硫酸根的检测限为1.0×10^-^2μg/ml,相对标准偏差为2.67%,回收率为97.5%,扩展了离子色谱法测定实际样品的范围。  相似文献   

11.
In a slightly acidic medium (sodium acetate-acetic acid buffer, pH 4) saccharin and Nile Blue form an ion-association compound which is extractable into methyl isobutyl ketone and allows the spectrophotometric determination of saccharin. At 630 nm Beer's law is obeyed over the saccharin concentration range 0.1-3.5 microg/ml in the aqueous phase and the apparent molar absorptivity is 5.8 x 10(4) l.mole(-1).cm(-1). The method shows good selectivity and can be applied to the determination of saccharin in artificial sweeteners, soft drinks and toothpastes.  相似文献   

12.
In this paper, the separation and determination of four artificial sweeteners (aspartame, sodium cyclamate, acesulfame-K and sodium saccharin) by ion chromatography coupled with suppressed conductivity detector is reported. The four artificial sweeteners were separated using KOH eluent generator. Due to the use of eluent generator, very low conductance background conductivity can be obtained and sensitivity of sweeteners has been greatly improved. Under the experimental condition, several inorganic anions, such as F-, Cl-, NO3-, NO2-, Br-, SO4(2)-, PO4(3)- and some organic acid such as formate, acetate, benzoate, and citrate did not interfere with the determination. With this method, good linear relationship, sensitivity and reproducibility were obtained. Detection limits of aspartame, sodium cyclamate, acesulfame-K, sodium saccharin were 0.87, 0.032, 0.019, 0.045 mg/L, respectively. Rate of recovery were between 98.23 and 105.42%, 99.48 and 103.57%, 97.96 and 103.23%, 98.46 and 102.40%, respectively. The method has successfully applied to the determination of the four sweeteners in drinks and preserved fruits.  相似文献   

13.
提出了比值导数波谱-多波长最小一乘回归分光光度法。该法能同时测定三组分混合物而毋需零交点波长和等吸收点,且回归稳健性好.可消除异常点的影响。方法用于合成样品和饮料中糖精钠、苯甲酸和山梨酸的同时测定,相对误差<± 3. 5%,回收率为 96. 6%~104.4%,相对标准偏差为2.0%~3.1%.  相似文献   

14.
《Analytical letters》2012,45(18):2129-2140
Abstract

A simple, rapid and sensitive spectrophotometric method has been developed for the determination of saccharin using azure C. Saccharin reacts quantitatively with azure C in citric acid buffer forming a blue product. The blue product can be extracted into chloroform, Beer's law is valid over the concentration range 3–75 ppm of saccharin and the molar absorptivity is 3.1 × 103 1 mol?1 cm?1. Reasonable amounts of ingredients that are likely to be present in soft drinks and pharmaceuticals do not interfere. Recoveries of saccharin from soft drinks and pharmaceuticals were satisfactory.  相似文献   

15.
A micellar electrokinetic capillary method for the simultaneous determination of the sweeteners dulcin, aspartame, saccharin, and acesulfame-K and the preservatives sorbic acid; benzoic acid; sodium dehydroacetate; and methyl-, ethyl-, propyl-, isopropyl-, butyl-, and isobutyl-p-hydroxybenzoate in preserved fruits is developed. These additives are ion-paired and extracted using sonication followed by solid-phase extraction from the sample. Separation is achieved using a 57-cm fused-silica capillary with a buffer comprised of 0.05 M sodium deoxycholate, 0.02 M borate-phosphate buffer (pH 8.6), and 5% acetonitrile, and the wavelength for detection is 214 nm. The average recovery rate for all sweeteners and preservatives is approximately 90% with good reproducibility, and the detection limits range from 10 to 25 microg/g. Fifty preserved fruit samples are analyzed for the content of sweeteners and preservatives. The sweeteners found in 28 samples was aspartame (0.17-11.59 g/kg) or saccharin (0.09-5.64 g/kg). Benzoic acid (0.02-1.72 g/kg) and sorbic acid (0.27-1.15 g/kg) were found as preservatives in 29 samples.  相似文献   

16.
建立了液相色谱~串联质谱测定冷冻饮品中环己基氨基磺酸钠的方法。冷冻饮品经净化、冷冻离心后用水稀释定容,采用C18色谱柱(50mm×2.1mm,1.7μm),以乙腈-0.01mol/L乙酸铵缓冲溶液为流动相,电喷雾离子源负离子模式(MRM)定性、定量测定环己基氨基磺酸钠。环己基氨基磺酸钠的质量浓度在2—1000μg/L范围内与峰面积呈线性关系,相关系数,=0.9999,方法的定量限为0.02mg/kg。在10—100μg/L范围内,3水平加标回收率为87.5%~101.8%,测定结果的相对标准偏差为3.0%(H=6)。该方法净化效果好,灵敏度高,能快速完成冷冻饮品中环己基氨基磺酸钠的测定。  相似文献   

17.
测定了同时测定两组分的多波多线性回归导数分光光度法,无需进行化学分离。方法用于模拟样品和饮料样品中糖精钠和苯甲酸的同时测定,回收率为98% ̄101%,相对标准偏差〈3.0%。  相似文献   

18.
Fo OF  Moraes AJ  Dos Santos G 《Talanta》1993,40(5):737-740
A rapid, precise and low cost method for saccharin determination in dietary products is proposed. Saccharin in several samples is potentiometrically titrated with mercurous nitrate solution using a silver wire coated with a metallic mercury film as the working electrode, and the end point was found using a Gran's plot. The detection limit of sodium saccharin was 0.5 mg/ml and the best pH range was from 2.0 to 3.5. Sucrose, glucose, aspartame, sodium cyclamate, sorbitol, fructose, benzoic acid, salicylic acid and lactose do not interfere even in significant amounts. The interference due to the presence of chloride and/or phosphate ions can be eliminated by previous solvent extraction of this sweetener. Recovery of saccharin from various dietary products gave from 95.2 to 103.2% of the label claim.  相似文献   

19.
Liu F  Wang Y  Wang Y  Zhou J  Yan C 《色谱》2012,30(3):292-297
建立了高效液相色谱-蒸发光散射检测仪(HPLC-ELSD)同时检测食品中安赛蜜、糖精钠、甜蜜素、三氯蔗糖和阿斯巴甜5种甜味剂的方法。甜味剂经0.1%(v/v)甲酸缓冲液提取后,利用C18固相萃取小柱净化浓缩,以3 μm C18柱为分离柱,0.1%(v/v)甲酸(氨水调节pH=3.5)-甲醇(61:39, v/v)为流动相,经高效液相色谱法分离,蒸发光散射检测器进行检测。结果表明,5种甜味剂在30~1000 mg/L的范围内,具有良好的线性关系(相关系数大于0.997);在3个添加水平下,样品的平均回收率为85.6%~109.0%,相对标准偏差小于4.0%;方法检出限(LOD,信噪比(S/N)=3)分别为安赛蜜2.5 mg/L、糖精钠3 mg/L、甜蜜素10 mg/L、三氯蔗糖2.5 mg/L及阿斯巴甜5 mg/L。该方法简单、灵敏、操作成本低,可用于不同形态食品中多种甜味剂的同时检测。  相似文献   

20.
稽超  孙艳艳  李秀琴  储晓刚  陈正行 《色谱》2009,27(1):111-113
建立了采用超高效液相色谱同时测定饮料中4种甜味剂(安赛蜜、糖精钠、甜味素、纽甜)的方法。样品经简单的预处理后,通过ACQUITY UPLCTM BEH C18色谱柱分离,以乙腈-20 mmol/L磷酸二氢钠水溶液为流动相进行梯度洗脱,于220 nm波长下紫外检测。一次进样分析仅需6 min。4种甜味剂在0.5~20.0 mg/L范围内的线性关系良好,在加标水平为1,10和20 mg/L时,被测物的回收率为80.5%~95.2%,相对标准偏差为0.50%~8.7%。  相似文献   

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